This invention relates to a two stroke diesel engine and more particularly to an improved arrangement for lubricating such an engine and avoiding induction system noise.
It is well known in two cycle crankcase compression engines and particularly those of the diesel type to supply the intake charge to the crankcase chambers through an induction passage that incorporates a check valve, normally of the reed valve type. The reason for the check valve is to insure that none of the intake charge is forced back out of the crankcase chamber during certain portions of the piston stroke. The reed type check valve is particularly advantageous for use in conjunction with such applications.
It is also known that there is a necessity for supplying lubricant to the engine and frequently this is done by mixing oil with the fuel in intake charge so as to lubricate the engine parts such as the connecting rod bearing and crank shaft journals. However, in such an arrangement the burned oil becomes the cause of blue smoke particularly at low loads which is objectionable. It has been proposed, therefore, to apply a separate lubricating system that will deliver lubricant directly to the components of the engine without introducing it through the intake charge. When this occurs and the engine has direct fuel injection, as is common with a diesel engine, however, the reed type check valve operates only on induction system air and the opening and closing of the valve plates can give rise to a slapping noise which may be objectionable under running conditions.
It is, therefore, a principal object of this invention to provide an improved lubricating and valving system for a two cycle diesel engine.
It is a further object of this invention to provide an improved arrangement for lubricating a two cycle internal combustion engine and, at the same time, avoiding the noise of the reed type valve in the induction system.
It is a further object to this invention to provide an arrangement for providing sufficient lubricant to a reed type valve to avoid noise during its closing operation but without causing the effect of blue smoke in the exhaust of the engine.